Conditioning of Feed Material Prior to Feeding: Approaches for a Sustainable Phosphorus Utilization

Abstract

A circular phosphorus (P) bioeconomy is not only worthwhile for conserving limited mineral P reservoirs, but also for minimizing negative environmental impacts caused by human-made alterations. Although P is an essential nutrient, most of the P in concentrates based on cereals, legumes and oilseed byproducts is organically bound to phytate. The latter cannot be efficiently utilized by monogastric animals and is therefore diluted into the environment through the manure pathway. This review examines various strategies for improved P utilization in animals and reflects the respective limitations. The strategies considered include feeding of debranned feedstuffs, pre-germinated feed, co-feeding of phytase and feeding material with high native phytase activity. All these approaches contribute to an improved P bioavailability. However, about half of the organic P content continues to be excreted and therefore remains unused by the animals. Nevertheless, technologies for an efficient utilization of P from cereal-based feed already exist; however, these are not industrially established. Conditioning feed material prior to feeding fosters P-reduced feed; meanwhile, P bound to phytate can be recovered. Based on known techniques for P separation and solubilisation from cereal products and phytate conversion, potential designs for feed material conditioning processes are proposed and evaluated.

Comparison of Phosphorus and Phytase Activity Distribution in Wheat, Rye, Barley and Oats and Their Impact on a Potential Phytate Separation

“…Industrial approaches for a mechanical P separation within the bran or whole grain meal are not established or published yet. All other investigations on P reduction in grains focus on wet-phase processes by either activation of intrinsic grain enzymes or hydrolysis through external enzymes (Herrmann et al, 2020;March et al, 1998;Widderich et al, 2022). The treatment of a pre-separated P rich layer can significantly reduce energy costs and the amount of process media needed compared to a direct enzyme treatment of whole grains as less mass is used for the wet-phase process.…”

Phytase production by white-rot fungi cultivated in liquid medium with particulate agro-industrial byproducts

“…Phytic acid has been reported with anti-nutritional activity because it chelates cations, an issue for swine and poultry farming. Moreover, the phytate in the livestock feed alters the secretion of endogenous compounds such as animal digestive enzymes, HCl, and mucin, which further reduces nutrient availability (VASUDEVAN et al, 2019;WIDDERICH et al, 2022). The feed costs for swine and poultry production account for about 60-70% of total livestock production costs, and around 25% of the feed is released through feces, a difficult-to-treat effluent with a high environmental impact (RAVINDRAN, 2013).…”

ATR-FT-MIR Based Inline Analysis for Determination of Phytate in Plant Residuals During Wet-Treatment

“…In livestock nutrition phosphorus (P) is an essential nutrient but often limited in availability [1]. P is stored by the plant in organically bound form as phytic acid (inositol-1,2,3,4,5,6-hexakisphosphate, InsP 6 ) or its corresponding salt phytate in a condensed form [2].…”

“…Nevertheless, due to unfavorable conditions in the intestinal tract, only up to 50% of the InsP 6 is digested [10]. Besides the application of exogenous enzymes, metabolically triggering the germination process by wet-treatment can effectively reduce phytate content in feed material [1]. The effectiveness of phytate degradation is a species-dependent phenomenon, which is connected to endogenous phytase activity and is comparatively high in rye bran [1].…”

“…Besides the application of exogenous enzymes, metabolically triggering the germination process by wet-treatment can effectively reduce phytate content in feed material [1]. The effectiveness of phytate degradation is a species-dependent phenomenon, which is connected to endogenous phytase activity and is comparatively high in rye bran [1]. It was shown that activation of intrinsic enzymes can completely eliminate phytate content in rye bran [12].…”